coldlegs
30-01-2015, 07:38 PM
Decided to try out some semi-widefield narrowband imaging so bought an old Skywatcher 120ST/F5 refractor from Gav(GC-South Aust) and did three hours of five minute Ha subs as a test to see how eggy the edges of the field of view were. Surprisingly, only the corners were seriously eggy and I don't think I'll bother with a straight out flattener but I noticed Televue had one (the TRF2008) that was also a 0.8x reducer. Supposed to work for 400mm-600mm FL refractors so it would probably be optimised for the radius of curvature of a 500mm scope and with a certain error be respectable at 600mm. If it worked even with some eggy bits at the edges the scope would give me an even wider field of view at F4. Has Anyone tried a TRF2008 on a 120mm f5 refractor ? I would be very interested to hear from anyone who has.
Cheers
Stephen
Photo
NGC 2234 end of Carina nebula
QHY9M camera
Baader Ha filter
39x5min subs
Cheers
Stephen
Photo
NGC 2234 end of Carina nebula
QHY9M camera
Baader Ha filter
39x5min subs